1. Field of the Invention
This invention relates to food products and methods for producing them. More specifically, this invention relates to a vitamin enriched ready-to-eat cereal made by a method wherein a dry vitamin premix and beta carotene are homogeneously admixed into the cooked cereal mass before piece forming and finish drying.
2. Description of the Prior Art
Breakfast cereal products are often enriched with vitamins. In known methods for making R-T-E cereals prepared from cooked cereal doughs, vitamins are generally applied in two separate portions. A first portion consisting of heat tolerant vitamins are generally incorporated into the cooked cereal dough. A second portion comprising heat sensitive or heat labile vitamins are generally sprayed onto the finished cereal pieces after pelleting, pellet shaping, drying, and toasting.
In order to topically apply the heat sensitive vitamins, a dry premix of the heat sensitive vitamins is mixed into a solution and sprayed onto the cereal pieces. Spraying the multivitamin solution onto the cereal pieces after such hot process steps as drying, toasting, baking, etc., prevents heat sensitive vitamins from degradation during these hot process steps. Vitamin degradation from cooking steps is particularly undesirable because of the formation of distasteful odors and flavors as well as the loss of heat labile vitamin activity.
While effective for certain vitamin types, the topical application of a vitamin solution is not without certain disadvantages. For instance, one problem is that topically applied vitamins can cause an undesirable flavor for the cereal piece When so applied on the surface area of the cereal pieces, the vitamin(s) are in direct contact with the cereal consumer's tongue upon consumption. With cereal products such as toasted flake cereal products having a high surface area, the amount of vitamins which come into contact with the consumer's tongue during consumption is increased. While applying a frosting to the cereal pieces after the vitamin solution has been sprayed onto the cereal pieces is helpful in masking the flavor of the vitamins, this process can also dilute the vitamin content present upon the cereal pieces.
Still another problem is vitamin ingredient loss during application. Vitamins are very expensive ingredients. Unfortunately, topical vitamin application can involve substantial physical loss of the vitamins upon application since not all the spray hits the cereal but also coats the application vessel, transport belts, etc. Typically, for every pound of vitamins consumed in the manufacturing process perhaps as little as 0.5 lb. ends up in the final dry cereal product.
Another problem is that once applied on or incorporated into an R-T-E cereal, vitamins can exhibit deterioration or loss of potency/bioavailability upon the extended storage typical of R-T-E cereal commercial distribution.
The prior art, of course, contains numerous teachings which attempt to overcome one or more of the above-noted problems.
For example, U.S. Pat. No. 3,767,824 to Keyser et al. discloses a method of coating cereal products with vitamins. This process requires that a cereal grain be precooked, dried, and formed into particles. The cereal particles are then coated with vitamins The vitamins are prepared in a fatty composition before their application to the cereal particles. The '824 patent states that the addition of vitamins to a cereal dough is old and undesirable. The reason stated for the undesirability of premixing vitamins into a cereal dough is that the vitamins are deactivated during the cooking step.
U.S. Pat. No. 2,345,571 to Briod et al. discloses processes for producing a vitamin fortified, dry product. The processes according to this invention require that a fat soluble vitamin composition be added to an aqueous slurry of a vegetable material. The examples in this patent indicate that the fat soluble vitamin composition is a liquid, oleaginous mixture. The vitamin composition is not added to the vegetable material in a dry powder form.
U.S. Pat. No. 1,575,762 to Hoffman et al. discloses a method of adding dry vitamins, namely, B vitamins, to a bread dough. This method requires devitalizing a yeast and then drying the yeast without rupturing cell walls. The resulting product is added to another food product to supplement its vitamin content. The '762 patent is only concerned with vitamins contained in yeast and not dry powder vitamin mixtures. Additionally, the '762 patent is only concerned with enriching the vitamin B content in foods.
U.S Pat. No. 2,775,521 to Mateles et al. discloses a method for fortifying grain products with dry mixtures of vitamins and minerals. This patent is concerned with coating the grain product with a vitamin coating. The product of this patent is subject to the same problems of undesirable flavor and color variations due to the topical coating of the vitamin on the food product. This patent does not disclose a method for incorporating or distributing the vitamin into the cereal grain mass of the food product.
U.S. Pat. No. 2,497,035 to Seeder discloses a process of preparing a vitamin C enriched baked product. The method of the '035 patent involves adding either dry or wet ascorbic acid to a dough which is then baked. This patent is unconcerned with preparing a cereal product or a product enriched by any vitamins other than vitamin C.
U.K. published patent application Ser. No. B493,950 to Borenstein et al. discloses a composition in which dry vitamin A in powder form is added to a flour. The flour can then be used to prepare baked goods. This patent is unconcerned with the enriching of a cereal product with a dry multivitamin mixture.
As serious as these problems are for heat sensitive vitamins generally, the particular problem associated with the potential fortification of beta carotene overshadows these everyday problems. Unfortunately, R-T-E cereals that have been topically fortified with beta carotene exhibit extremely rapid loss or deterioration in vitamin efficacy due to the extreme instability of beta carotene. While the stability of beta carotene is dependent upon a variety of factors such as temperature, humidity, light, etc., beta carotene appears to have particular sensitivity to oxygen. For this reason, vitamin supplements deliver beta carotene disposed within an opaque oxygen impermeable gelled capsule.
Still another problem that is particularly severe to beta carotene is that the topical application of beta carotene vitamin can result in undesirable stains in the form of red spots that appear on the surface of the cereal pieces. This highly visually unattractive mottled appearance is colloquially referred to as the problem of "fish-eyes." Consumers would immediately reject such a product as being visually unfit for consumption.
U.S. Pat. No. 4,764,388 issued Aug. 16, 1988 to Sullivan et al. discloses a method for preparing a vitamin enriched shredded wheat R-T-E cereal product. The method disclosed therein includes addition of a multiple vitamin mixture which includes selected heat sensitive vitamins, especially the B vitamin, that commonly are therefore topically applied as a dry mix after cooking the cereal grains but prior to shredding and finish hot process steps. However, the '388 patent does not describe the particular problems associated with beta carotene fortification. Also, the patent teaches away from the preferred method of vitamin fortification herein which involves separate addition of the beta carotene and other vitamins to the cooked cereal mass.
Given the state of the art as described above, there is a continuing need for new and improved vitamin fortified R-T-E cereals that include beta carotene fortification and methods for preparing such improved R-T-E cereals.
Accordingly, it is an object of this invention to provide a beta carotene enriched R-T-E cereal.
Another object of the present invention is to provide a method of incorporating or distributing a dry multivitamin premix into a cooked cereal dough before that cooked cereal dough is formed into cereal pieces.
It is a further object of the present invention to provide beta carotene fortified R-T-E cereals that exhibit surprising maintenance of vitamin availability levels even upon extended storage.
It is another object of the present invention to provide beta carotene fortified R-T-E cereals that are visually attractive and avoid mottled surface appearance.
It is another object of the present invention to provide methods for preparing beta carotene fortified R-T-E cereals that minimize the loss of the expensive beta carotene component.
Still another object of the present invention is to provide beta carotene fortified R-T-E cereals that exhibit minimal flavor problems associated with vitamin fortification.
Still another object of the present invention is to provide R-T-E cereal preparation methods that minimize degradation of vitamin activity during processing.
Another object of the present invention is to provide beta carotene and other vitamin fortified R-T-E cereals that exhibit extended beta carotene vitamin activity even upon extended room temperature storage.
It has been surprisingly discovered that the above objectives can be realized and superior vitamin fortified R-T-E cereal products can be prepared. The present improved R-T-E cereals are prepared by methods of R-T-E cereal preparation involving beta carotene incorporation into a cooked cereal mass prior to piece formation rather than by topical application after all hot processing steps. The objectives are achieved without sacrificing activity of the multivitamins and produces a multivitamin enriched R-T-E cereal product without an adverse effect on the flavor or appearance of the cereal product by the incorporated or distributed multivitamins and surprising efficacy and stability of beta carotene.